The present invention relates to a technology for managing the information concerning the volumes of a storage subsystem that is used by a computer or file system in a network environment where one or more servers (computers) and storage controllers (storage subsystems) exist, and more particularly to a technology for displaying actual volume usage by a specified computer or file system.
In recent years, the SAN (Storage Area Network) technology has attracted a good deal of attention as it reduces the storage management cost. In the SAN environment, a plurality of servers (computers) use a storage controller (storage subsystem), which is a dedicated storage device. More specifically, the volumes within a storage subsystem are assigned to the computers for their use.
Under these circumstances, the amount of storage use by corporations has increased year after year. It is therefore important that computer/storage subsystem capacity management be properly exercised. In a conventional computer capacity management, file system capacity deletion is prevented by monitoring the amount of file system use within a computer and the change in the available free space. As a method for acquiring the capacity information about individual computers, a technology for monitoring the capacity and performance of a plurality of computers is disclosed by U.S. Pat. No. 6,148,335.
In conventional storage subsystem capacity management, the unallocated storage space within a storage subsystem is monitored, for instance, to time the addition of a disk to the storage subsystem. Tools and other items for displaying the storage subsystem capacity information are commercialized by storage subsystem vendors and the like.
The above-described conventional methods are for monitoring either the computer side or storage subsystem side. In some cases, these methods are inadequate for determining the amount of actual use by a specific file system. In reality, various methods are used, depending on the data importance, to create redundant data as the data to be stored in a storage subsystem.
If, for instance, RAID (Redundant Arrays of Independent Disks) 1, RAID 5, or other similar parity data disks are used, a snapshot or mirror copy is created within a storage subsystem, or a backup is made in a remote storage subsystem or tape library, the amount of storage allocated to computers differs from the amount of storage used within the storage subsystem. In this instance, the conventional method for monitoring either the computer side or storage subsystem side cannot determine the amount of actual use by a specific file system.
When the above conventional method is used to determine the amount of actual use by a specific file system, the RAID structure, mirroring, remote copy, and other relevant configurations need to be acquired from individual computers and storage subsystem and then manually associated with each other by a storage administrator. These steps are troublesome to the storage administrator. Further, the steps to be performed for estimating the storage capacity required for file system capacity expansion in the above-mentioned structure are extremely complicated.